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Choosing a wood moisture meter

Too much moisture can make for a smoky mess

Sometimes you can tell by looking at it if your firewood is dry enough to burn, but to be sure, use a moisture meter.

If wood hasn’t cured enough, you’re in for all smoke and no fire. Burning green, damp wood in a fireplace is also bad news for your chimney. It causes an increased build-up of soot, tar and creosote. This raises the risk for a chimney fire.

Wood that’s been stacked for a year or so should be dry enough to burn. But if you aren't sure, test it with a moisture meter. It’ll tell you on-the-spot if it’s ready.

Paul Laurenzi is the vice president of marketing for a company that sells moisture meters and explains the basics of how they work.

"Most of them have two pins that are mounted right on top of the unit. And what happens is when you push those pins into the material, there is a reading that’s the actual resistance, or the conductivity between those two points, so it’s the electrical current between those two points. And then that is converted into a reading on either analog or digital display that is actual moisture content of wood," Laurenzi says.

Ideally, you want wood that has a moisture content of around 20%. If you burn a lot of wood and rely on it for most of your home heat, it might be worth investing in a moisture meter. Laurenzi says his product measures the moisture content anywhere from 6% to 30%, and costs around $145. You’ll find less expensive units in hardware stores but this might be a purchase where you get what you pay for.

There are a couple important features to pay attention to, especially the pins.

"They need to be very sharply tapered, they need to be you know a combination of being sharp, tapered and rugged so they can withstand a pretty demanding application because you’re actually pushing it into wood which is pretty tough," Laurenzi says. "I would look for design of the case so that you kind of hold the handle in the palm of your hand so you can use it as a bit of a leverage point to press into the wood."

It’s a good idea to take a couple of readings in different spots. Check in the middle and at the ends of a log for an idea of how wet or dry the wood is overall. There are adjustments for different species of wood because their drying rates will vary some.